Magnifications of paired micro-images emerging from a micro-lensing critical curve

Abstract

Studies of the inner regions of micro-lensed AGN during caustic crossing events have often relied upon the approximation that the magnification near a fold caustic is inversely proportional to the square root of the source-caustic distance. We examine here the behavior of the individual micro-images (one a micro-minimum, the other a micro-saddle) that emerge as a point source crosses a micro-fold caustic. We provide a variety of statistics on both the behavior of the two newly created micro-images, and some parameters which appear in higher order approximations for the magnification. We compare the predictions of these higher order approximations to the actual image magnifications of our simulations.

arXiv comment11 pages, 11 figures, 7 tables. Submitted to MNRAS

References in corpus (6)

• Identifying Lenses with Small-Scale Structure. II. Fold Lenses
• The Transverse Peculiar Velocity of the Q2237+0305 Lens Galaxy and the Mean Mass of Its Stars
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Cited by in corpus (1)

• Liverpool-Maidanak monitoring of the Einstein Cross in 2006$-$2019. I. Light curves in the $gVrRI$ optical bands and microlensing signatures